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PubMed2000

Suboptimal reproductive performance of dairy cattle kept in smallholder herds in a rural highland area of northern Tanzania.

The objectives of the present study were to assess the reproductive performance and cumulative incidence risk of reproductive disorders and to compare the success of artificial insemination (AI) to natural service (by handmating; NS) in dairy cattle kept in smallholder herds under a zero-grazing system in a rural highland area of Tanzania. Data on occurrence of all normal and abnormal reproductive events were collected for 215 adult animals belonging to 74 households. The median and range of the intervals: intercalving, calving to first service, and calving to pregnancy were 477 (335-860), 154 (38-486) and 206 (61-567) days, respectively. Breed and parity did not affect the reproductive parameters (P>0.05). However, cows in the milked group had a shorter median calving interval than those in the suckled group (P<0.001). The overall percentage pregnant and the percentage pregnant to first service were higher in the NS than in the AI group (49 vs. 32%; P=0.007) and (67 vs. 25%; P<0.001), respectively. The median numbers of services per pregnancy were not different between the AI (3) and NS (2) groups (P=0.17). The cumulative incidence risk of abortion, dystocia, prolapse, retained fetal membranes, mastitis, milk fever and cyclic non-breeders were 16.0, 1.7, 2.5, 4.2, 5.0, 1.7, and 6.1%, respectively. Hoof overgrowth (4.6%) and hoof deviation (4.6%) were the most-frequent digital problems. We concluded that reproductive parameters and cumulative incidence risk of abortion show suboptimal reproductive performance in rural-based, zero-grazed smallholder dairy herds in Tanzania particularly those using AI.

Abortion, Spontaneous↗
PubMed2000

Birth outcomes of women with ulcerative colitis: a nationwide Danish cohort study.

OBJECTIVE: Our study aimed to compare the birth outcomes in offspring of women with ulcerative colitis with controls without the disease. METHODS: A cohort study of 1531 newborns to mothers with ulcerative colitis, and 9092 controls, based on linkage between the Danish National Registry of Patients and the Danish Birth Registry from 1982 to 1992. RESULTS: Among the births to women with ulcerative colitis, 569 took place before and 962 after the first hospitalization for ulcerative colitis. We found no increased risk of either low birth weight or intrauterine growth retardation for newborns born before or after the mothers' first hospitalization. The risk of preterm birth was increased when birth occurred after the mothers' first hospitalization (odds ratio = 1.4, 95% confidence interval = 1.1-1.9), and particularly when the first hospitalization for ulcerative colitis took place during pregnancy (odds ratio = 3.4, 95% confidence interval = 1.8-6.4). CONCLUSIONS: In the offspring of women with ulcerative colitis, we found no increased risk of low birth weight or signs of intrauterine growth retardation. The risk of preterm birth was increased in the offspring of women with ulcerative colitis, particularly when the first hospitalization for ulcerative colitis occurred during pregnancy.

Adult↗
PubMed2004

Comparison of timed AI after synchronized ovulation to AI at estrus: reproductive and economic considerations.

A timed artificial insemination (TAI) protocol using OvSynch was compared to artificial insemination (AI) at detected estrus in 2 large dairy herds differing in reproductive management. Cows were synchronized for TAI starting at 62 and 42 d in milk in herds 1 and 2, respectively. The OvSynch regimen included: GnRH (buserelin) at 0.02 mg (i.m.) on d 0; PGF2alpha (tiaprost) at 0.75 mg (i.m.) on d 7; buserelin at 0.02 mg (i.m.) on d 9; and TAI 16 to 20 h later. After TAI, cows seen in estrus received AI, whereas cows diagnosed not pregnant were resynchronized for TAI. Control cows received AI based on detected estrus after voluntary waiting periods of 72 d in herd 1 and 50 d in herd 2. An economic analysis included costs associated with days open, culling, AI, synchrony products, treatment, and examinations. A sensitivity analysis of those variables determined effects on total costs per pregnancy. Use of OvSynch reduced intervals to first AI and days open in both herds and reduced culling for infertility in herd 2. Conception rates for first AI at detected estrus were significantly higher compared to TAI in both herds and for overall AI at estrus in herd 2. For groups assigned to AI at estrus, mean 21-d submission rates over 200 d for AI were higher in herd 1 than in herd 2 (55.6 vs. 28.6%). Days open and culling were the major cost factors. Although OvSynch improved reproduction in both herds, AI based on detected estrus was economically superior in herd 1, whereas OvSynch was superior in herd 2. This was consistent across ranges of cost factors evaluated. Evaluation of synchrony protocols should include reproductive performance along with appropriate costs associated with treatments. Such costs may offset benefits to reproduction in herds with good estrous detection rates.

Animals↗
PubMed1993

Serum placental protein 14 concentrations in the first trimester of ovum donation pregnancies.

The concentration of the endometrial glycoprotein placental protein 14 (PP14) has been measured at weekly intervals during the first trimester in serum obtained from women who had become pregnant naturally (n = 15, all singleton) or following ovum donation (n = 16, 15 singleton and one twin) after ovarian failure (n = 13), Turner's syndrome (n = 2) or post-chemotherapy (n = 1). The concentration of PP14 failed to rise in ovum donation pregnancies, and was significantly reduced compared to the concentration in natural conceptions from 5 to 13 weeks gestation (P < 0.05-0.01). These findings demonstrate that the corpus luteum is essential for the normal increase in serum PP14 in the first trimester. Furthermore, they suggest that progesterone is not the major stimulus to PP14 synthesis in early pregnancy.

Female↗
PubMed2006

Association of cytochrome P450 1B1 polymorphism with first-trimester miscarriage.

OBJECTIVE: To determine whether the cytochrome P450 1B1 (CYP1B1) Val432Leu polymorphism is associated with risk of miscarriage. We also analyzed the possible interaction between this polymorphism and caffeine intake. DESIGN: The population-based case-control study included 507 women with miscarriage in the first trimester of pregnancy and 908 controls with a normal first-trimester pregnancy. The controls were frequency matched to cases. The material was analyzed taking maternal age, smoking habits, alcohol intake, caffeine intake, fetal karyotype, nausea, and vomiting into consideration. SETTING: University hospital and primary care facility. MAIN OUTCOME MEASURE(S): CYP1B1 Val432Leu genotype frequencies in cases and controls. RESULT(S): Carriers of the CYP1B1 432 Val/Val genotype were at a higher risk of miscarriage in the first trimester of pregnancy (odds ratio = 1.46; 95% confidence interval, 1.02-2.08). We also found a significant interaction between genotype and caffeine intake. CONCLUSION(S): CYP1B1 Val432Leu polymorphism is associated with first-trimester miscarriage, and it may also modify the risk among coffee drinkers.

Abortion, Spontaneous↗
PubMed2002

The recurrence risk of adverse outcome in the second pregnancy in women with rheumatic disease1.

OBJECTIVE: To study recurrence risks of adverse pregnancy outcome in the second pregnancy in women with rheumatic disease. METHODS: In a national population-based cohort study, women with rheumatic disease recorded from 1967 to 1995 in the Medical Birth Registry of Norway were compared with mothers without such diagnoses with regard to recurrence risks of adverse pregnancy outcomes in the second pregnancy. The odds ratios (ORs) of all outcomes were adjusted for maternal age, those of cesarean delivery for time period, and those of preeclampsia for interpregnancy interval. RESULTS: Women with rheumatic disease an dadverse pregnancy outcome in the first pregnancy had a statistically significant higher recurrence risk of the same event in the second pregnancy than women without rheumatic disease (preeclampsia: OR 2.22; 95% confidence interval [CI] 1.18, 4.19) (cesarean delivery: OR 1.52; 95% CI 1.05, 2.21) (preterm birth: OR 1.86; 95% CI 1.12, 3.11). In women with rheumatic disease diagnosed between the first and second births, a significantly increased recurrence risk of low birth weight occurred. Women with rheumatic disease also had a higher occurrence of markers for placental dysfunction (preeclampsia, preterm birth, or small for gestational age) in the second birth after any of these outcomes in the first birth (OR 1.35; 95% CI 1.02, 1.78) (35.1% versus 29.2%). CONCLUSION: The recurrence risk of an adverse outcome in the second pregnancy is increased in any woman, but was even higher in women with a rheumatic disease. These patients should be counseled accordingly, be closely monitored during pregnancy, and have access to appropriate subspecialists.

Adult↗
PubMed2004

Paternity change and the recurrence risk in familial hypertensive disorder in pregnancy.

OBJECTIVE: To investigate if there is an increased risk for recurrence of hypertensive disorder in pregnancy with a new partner and whether this is affected by maternal age and the interbirth interval through use of familial material. METHODS: Data on 614 multiparous women, with confirmed de novo hypertensive disorder in a first pregnancy, were used to assess the effect of paternity and interbirth interval on recurrence of hypertensive disorders. RESULTS: There were 121 women (19.7%) who had changed partner. Recurrent hypertension occurred in 318 women (64.5%) with the same partner and in 75 women (62%) with a new partner. The odds ratio (OR) for recurrence with the same partner was 1.115 (95% CI 0.739-1.680) and with a new partner 0.897 (95% CI 0.595-1.353). The mean interbirth interval was longer for women with recurrent hypertension (4.9 vs. 4.0 years, p = 0.0002). The OR for developing recurrent hypertensive disorder was 1.154 (95% CI 1.049-1.269) for every interval year with the same partner and 1.145 (95% CI 0.958-1.368) with a new partner after correction for maternal age. CONCLUSION: In women with a positive family history and previous hypertension in pregnancy, change of paternity does not influence the risk of recurrence. Increasing interbirth interval may account for a 15% recurrence risk for each year, independent of maternal age. There was no indication that a change of partner conferred any influence on the recurrence risk that is not explained with birth interval or age.

Female↗
PubMed2000

An evaluation of poor pregnancy outcomes among Burundian refugees in Tanzania.

CONTEXT: Little is known about pregnancy outcomes among the approximately 11 million refugees worldwide, 25% of whom are women of reproductive age. OBJECTIVE: To estimate incidence of and determine risk factors for poor pregnancy outcomes and to calculate the contribution of mortality from neonatal and maternal deaths to overall mortality in a refugee camp. DESIGN: Cross-sectional review of records and survey, conducted in February and March 1998. SETTING: Mtendeli refugee camp, Tanzania. PARTICIPANTS: For the overall assessment, 664 Burundi women who had a pregnancy outcome during a recent 5-month period (September 1, 1997-January 31, 1998) and their 679 infants; 538 women (81%) completed the survey. MAIN OUTCOME MEASURES: Incidence of fetal death (fetus born > or =500 g or > or =22 weeks' gestation with no signs of life), low birth weight (<2500 g), neonatal death (death <28 days of life), and maternal death (deaths during or within 42 days of pregnancy from any cause related to or aggravated by the pregnancy or its management). RESULTS: The fetal death rate was 45.6 per 1000 births, the neonatal mortality rate was 29.3 per 1000 live births, and 22.4% of all live births were low birth weight. Compared with women without poor pregnancy outcome, those with poor pregnancy outcome were more likely to report prior high socioeconomic status (adjusted odds ratio [OR], 1.6; 95% confidence interval [CI], 1.1-2.4), having a first or second pregnancy (OR, 2.2; 95% CI, 1.4-3.4), and having 3 or more episodes of malaria during pregnancy (OR, 2.0; 95% CI, 1.4-3.1). Neonatal and maternal deaths accounted for 16% of all deaths during the period studied. CONCLUSIONS: Poor pregnancy outcomes were common in this refugee setting, and neonatal and maternal deaths, 2 important components of reproductive health-related deaths, contributed substantially to overall mortality.

Adult↗
PubMed1993

Socio-cultural determinants of child mortality in southern Peru: including some methodological considerations.

Among Amerindian children living at high altitude in the Andes in southern Peru, high child mortality rates have been reported in the literature, especially in the perinatal and neonatal period. We compared mortality rates in children calculated from retrospective survey data in 86 rural families from 2 Aymara and 3 Quechua peasant communities living at the same level of altitude (3825 m) in southern Peru. Relations between land tenure, socio-cultural factors and child mortality were studied, and methodological considerations in this field of interest are discussed. Checks on consistency of empirical data showed evidence for underreporting of neonatal female deaths with birth order 3 and more. Perinatal (124 vs 34 per 1000 births) and infant mortality (223 vs 111 per 1000 live births) was significantly higher in Aymara compared with Quechua children, but no difference was found after the first year of life. A short pregnancy interval was associated with an elevated perinatal and infant mortality rate, and a similar albeit insignificant association was found with increased maternal age. Amount of land owned and birth order were not related with child mortality. Although levels of maternal education are generally low in both cultures, a consistent decline in infant and child mortality was found with the amount of years mothers had attended school. However, the results suggest a U-shaped relationship between the amount of years of parental education and perinatal mortality in offspring. Late fetal and early neonatal mortality were particularly high in one Aymara community where mothers were found to have more years of education. Infanticide, a known phenomenon in the highlands of the Andes, is discussed in relation with the findings of the study. Although maternal and child health services are utilized by the majority of families in 4 of 5 study communities, 43 of 51 mothers under the age of 45 years reported that they delivered their last baby in the absence of traditional midwives or official medical supervision.

Adult↗
PubMed2006

First cesarean birth and subsequent fertility.

OBJECTIVE: To determine whether cesarean delivery is independently associated with later subfertility. DESIGN: Retrospective cohort study. SETTING: Maternity records kept for Scotland, 1980-1999. PATIENT(S): The study included 109,991 women who had first births between 1980 and 1984, excluding multiple or preterm births and perinatal deaths. INTERVENTION(S): Exposures studied were spontaneous vaginal birth, operative vaginal birth, planned cesarean delivery for breach presentation, planned cesarean delivery for other indications, and emergency cesarean delivery. MAIN OUTCOME MEASURE(S): The relative risk of not having a second pregnancy over the following 15 years, the interpregnancy interval, and the number of spontaneous early pregnancy losses between the first and second birth. RESULT(S): Women who delivered by planned cesarean section for breech presentation had an increased risk of not having a second birth compared with women whose first birth was a spontaneous vertex delivery (relative risk [RR]: 1.21, 95% confidence interval [CI]: 1.14 to 1.29). However, after adjustment for maternal and obstetric characteristics, there was no longer a strong association (adjusted RR: 1.07, 95% CI: 1.00 to 1.15). Operative vaginal delivery (forceps and vacuum extraction) and all types of cesarean delivery were associated with longer interpregnancy intervals. There was no relationship between mode of delivery and the number of spontaneous early pregnancy losses between the first and second birth. CONCLUSION(S): It is unlikely that delivering by cesarean section in a first pregnancy decreases a woman's likelihood of having a second viable pregnancy.

Abortion, Spontaneous↗
PubMed1981

Luteal phase pregnancies in female sterilization patients.

Little is known of the incidence, predictors or outcomes of luteal phase pregnancies (LPPs) in women presenting for voluntary interval female sterilization. A series of 37 LPPs was identified from a large multicenter female sterilization data set. Each LPP case was matched with two nonpregnant (NP) controls for clinic, operator, surgical approach, tubal occlusion technique and date of surgery. The LPP cases did not have a distinct demographic or clinical profile, but were generally more fecund than NP controls. LPPs were further compared with a second unmatched group consisting of 123 true sterilization failures (TSFs), pregnancies conceived after sterilization. Women with LPPs were more likely to have their pregnancies confirmed and/or terminated in the second trimester than were women with TSFs. The majority of LPPs were carried to term; the majority of TSFs ended in induced abortion. There were 12 ruptured ectopic pregnancies among the TSFs and none among the LPPs. Programmatic implications of the results are discussed.

Abortion, Induced↗
PubMed2002

Vigorous leisure activity and pregnancy outcome.

BACKGROUND: Preterm birth is the leading cause of perinatal mortality in North America and Europe and a major predictor of neonatal and infant morbidity. Postterm birth is associated with increased infant mortality and morbidity, as well as increased frequency of surgical or induced labor. Because vigorous leisure activity may affect timing of delivery, this study examined association between vigorous leisure activity and birth outcomes. METHODS: Women (N = 1,699) with a singleton pregnancy were recruited at 24-29 weeks' gestation from prenatal clinics in central North Carolina between 1995 and 1998. The type and duration of any regular vigorous leisure activity was assessed in a telephone interview covering the 3-month period before pregnancy and during the first and second trimesters of pregnancy. RESULTS: The prevalence of vigorous leisure activity was 22% before pregnancy, 14% during the first trimester, and 8% during the second trimester. Vigorous leisure activity before pregnancy was unrelated to preterm (<37 weeks) as compared with term delivery (37 to <42 weeks). The risk of preterm birth was somewhat reduced with vigorous leisure activity during the first trimester (odds ratio = 0.80; 95% confidence interval = 0.48-1.35) and more so during the second trimester (odds ratio = 0.52; 95% confidence interval = 0.24-1.11). Vigorous leisure activity before pregnancy or during the first or second trimester was not associated with postterm delivery (>/=42 weeks). CONCLUSIONS: Vigorous leisure activity during the first trimester, and even more so in the second trimester, was associated with a reduced risk of preterm birth. There was no association with postterm birth. To address the etiologic role of activity on pregnancy outcome and to overcome self-selection, a randomized clinical trial would be needed.

Female↗
PubMed2005

The influence of pregnancy on arterial compliance.

OBJECTIVE: To examine the effect of pregnancy and the interval between pregnancies on arterial compliance as measured by mean arterial pressure (MAP) and pulse pressure. METHODS: We conducted a 3-month chart review of deliveries at a tertiary care hospital (index pregnancies). Data collected included demographics, obstetric history, blood pressures, prepregnancy weight, weight gain, and neonatal outcome. If a subject's first delivery occurred at our institution, these records were reviewed in a similar fashion. Mean antepartum MAP and pulse pressure were calculated and compared for each trimester between index and first pregnancies. Statistical methods employed included repeated measures analysis of variance, repeated measures analysis of covariance, and correlation analysis. RESULTS: Two hundred eighty-five charts were reviewed. Forty-seven women had complete data covering both index and first pregnancy. Mean arterial pressure was significantly higher in all trimesters of first compared with index pregnancies (first pregnancy-first trimester 82.0 +/- 8.1 mm Hg, index pregnancy-first trimester 79.4 +/- 7.6 mm Hg, P = .032; first-second trimester 81.6 +/- 6.7 mm Hg, index-second trimester 78.7 +/- 6.6 mm Hg, P = .016; first-third trimester 83.9 +/- 6.9 mm Hg, index-third trimester 81.6 +/- 6.9 mm Hg, P = .047). Repeated measures analysis of covariance confirmed that pregnancy order contributed independently to differences in MAP. The interval between pregnancies was found to be inversely related to the difference in MAP from first to index pregnancies by trimester (r = -0.41, P = .004) and the change in MAP within pregnancy from first to third trimester (r = -0.31, P = .046). CONCLUSION: Mean arterial pressure is reduced in subsequent pregnancies compared with first pregnancies. This raises the possibility that pregnancy plays a role in modifying cardiovascular compliance. Consistent with this, the effect has temporal limitations in that the shorter the interval between pregnancies, the greater the reduction in MAP.

Adult↗
PubMed1996

Smoking reduces fecundity: a European multicenter study on infertility and subfecundity. The European Study Group on Infertility and Subfecundity.

Several studies published within the past 10 years indicate that smoking reduces fecundity, but not all studies have found this effect, and smoking cessation is not used routinely in infertility treatment in Europe. The present study was designed to examine male and female smoking at the start of a couple's waiting time to a planned pregnancy. Two types of samples were used: population-based samples of women aged 25-44 years who were randomly selected in different countries from census registers and electoral rolls, in which the unit of analysis was the couple; and pregnancy-based samples of pregnant women (at least 20 weeks' pregnant) who were consecutively recruited during prenatal care visits, in which the unit of analysis was a pregnancy. More than 4,000 couples were included in each sample, and 10 different regions in Europe took part in data collection. The data were collected between August 1991 and February 1993 by personal interview in all population-based samples and in all but three regions of the pregnancy sample, where self-administered questionnaires were used. The results based on the population sample showed a remarkably coherent association between female smoking and subfecundity in each individual country and in all countries together, both with the first pregnancy (odds ratio (OR) = 1.7, 95% confidence interval (CI) 1.3-2.1, at the upper level of exposure) and during the most recent waiting time to pregnancy (OR = 1.6, 95% CI 1.3-2.1). Results based on the pregnancy sample were similar (OR = 1.7, 95% CI 1.3-2.3). No significant association was found with male smoking (in the population sample, OR = 0.9, 95% CI 0.7-1.1 (first pregnancy) and OR = 1.0, 95% CI 0.9-1.3 (most recent waiting time); in the pregnancy sample, OR = 0.9, 95% CI 0.7-1.1). The fecundity distribution among smokers appeared to be shifted toward longer waiting times without a change in the shape of the distribution. Women who have difficulty conceiving should try to stop smoking or to reduce their smoking to less than 10 cigarettes per day.

Adult↗
PubMed1995

[The volumetric changes of uterine myomas in pregnancy].

Thirty-six pregnant women with a single uterine myoma were submitted to US at 2 and 4 weeks' intervals. The first US examination was made in 12 patients before pregnancy and in the other 24 patients between 9 and 12 weeks' gestation. The changes in the volume of myomas were analyzed in different periods of pregnancy. Thirty-four women underwent US in puerperium, four weeks after delivery: the myomas were smaller, possibly back to their initial volume. In 11 patients (31.6%), the myomas grew bigger during pregnancy, particularly during the first trimester. A statistically significant change in volume was observed between the first and the third trimester of pregnancy (p < 0.001). When investigating myoma growth in greater detail in the first trimester, we observed that the greatest increase in myoma volume occurred before the 10th gestational week. Three different categories of myoma volume were considered (p < 100 cc, 100-200 cc, > 200 cc) and related to myoma growth in each period. No relationship was observed between myoma volume and myoma growth.

Female↗
PubMed2002

Nuchal translucency measurements in consecutive normal pregnancies. Is there a predisposition to increased levels?

OBJECTIVE: The current study aims to assess the relative risk of isolated increased nuchal translucency (NT) in consecutive normal pregnancies. METHODS: A retrospective search of the fetal medicine unit database in which NT assessment was conducted. Only singleton fetuses with an unremarkable pregnancy outcome were included in this study. The repeated NT either at a threshold of >2.5 mm or > or =95th centile of the normal range for various CRLs (2 mm at a CRL < or =44 mm to 2.85 mm at CRLs 83-84 mm) was assessed. Pearson's correlation was applied to investigate any correlation between a log(10) NT obtained in two consecutive pregnancies. The chance of an increased NT in the first pregnancy followed by similar results in the subsequent one was assessed using Fisher's exact test. RESULTS: Ninety-two pregnant women with two consecutive normal pregnancies were identified. There was a highly significant correlation between the log(10) NT values measured in the consecutive pregnancies (r = 0.38; p < 0.001). The relative risk of an isolated NT > or =2.5 mm in the first pregnancy to be followed by a similar finding in the subsequent one was 18.21 (95% confidence interval [CI]: 3.62-91.55). The relative risk of an isolated NT > or =95th centile in the first pregnancy to be followed by a similar result in the subsequent one was 21 (95% CI: 4.53-97.44). CONCLUSION: The current results indicate a significant correlation of NT values in consecutive unaffected pregnancies. There also was a predisposition for a repeated isolated increased NT in subsequent pregnancies. Additional series and more information are needed before firm conclusions can be made.

Adult↗
PubMed2004

Effects of abnormal ovarian cycles during pre-service period postpartum on subsequent reproductive performance of high-producing Holstein cows.

The primary objective of this study was to investigate the effects of abnormal ovarian cycles during the pre-service postpartum period on subsequent reproductive performance of high-producing Holstein cows. The study was conducted in a commercial dairy farm with approximately 150 lactating cows, in a subtropical region of Japan. Animals were kept in free-stall barn, and fed a total mixed ration. Cows that calved from June 2001 to July 2002 were included in the study. Milk samples were collected twice weekly from 2 to 11 weeks postpartum, and progesterone concentrations in skim milk were determined by ELISA. After a voluntary waiting period of 40 days, cows detected in estrus were bred by artificial insemination (AI). Pregnancy was confirmed by palpation per rectum 40-70 days after AI. Out of a total of 91 cases, 39 (42.9%) had normal ovarian cycles (ovulation within 45 days after calving, followed by normal ovarian cycles), 32 (35.2%) had prolonged luteal phase (i.e. luteal activity for >20 days), and 12 (13.2%) had anovulation or delayed first ovulation (i.e. first ovulation did not occur until >45 days after calving). The remaining (8.8%) had other types of abnormalities. When compared with cows with a normal ovarian cycle, prolonged luteal phase cows had a lower 100 days AI submission rate, conception rate and pregnancy rate (84.2% versus 56.3%; P<0.05, 50% versus 16.7%; P<0.05 and 42.1% versus 9.4%; P<0.01, respectively), and longer intervals to first AI and to conception ( 67+/-6 days versus 98+/-7 days and 95+/-9 days versus 136+/-11 days; P<0.01 for each). Similarly, when compared with cows with normal ovarian cycles, those with anovulation had lower 100 days conception rate and pregnancy rate (50% versus 0%; P<0.05 and 42.1% versus 0%; P<0.01, respectively), and longer intervals to first AI and to conception ( 67+/-6 days versus 93+/-12 days; P<0.05 and 95+/-9 days versus 155+/-14 days; P<0.01, respectively). Survival analysis of the data for calving to conception interval showed that cows with prolonged luteal phase or anovulation were getting pregnant at a slower rate, and took longer to get pregnant than the cows with normal resumption of ovarian cyclicity postpartum. In conclusion, abnormal ovarian cycles during the pre-service period postpartum adversely affected reproductive performance, including AI submission rate, pregnancy rate, interval to first AI, and calving to conception interval in high-producing Holstein cows.

Animals↗