SEARCH · PubMed Health

Results for “First Pregnancy Intervals”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 217 records · Page 12Linked to original sources

PubMed1993

Relationship between herd calving to conception interval and culling rate for failure to conceive.

The factors affecting herd calving to conception intervals and culling rate are the interval to first service, the efficiency of heat detection, the pregnancy rate and the maximum number of oestrous cycles allowed to occur before the cow is considered to be so far into lactation that even if it does conceive, the length of the dry period and the delay to the next calving will make its production uneconomic. Depending on the fertility factor (the product of the average herd pregnancy rate and the oestrus detection rate) it is the maximum number of oestrous cycles, usually dictated by the length of the calving interval desired, that decides the outcome. A graphical representation of these mathematical relationships demonstrates methods for achieving different economic and other objectives.

Animal Husbandry↗

PubMed1989

Induced abortion and the risk of subsequent ectopic pregnancy.

This study assessed the effect of legal induced abortion on ectopic pregnancy risk by using a comparison group of reproductive-age women who were at risk of becoming pregnant during the same time period the women with ectopic pregnancy conceived. Cases were members of Group Health Cooperative of Puget Sound who were hospitalized for ectopic pregnancy from October 1981 through September 1986 (N = 211). Controls were randomly selected members matched to cases on age and county of residence (N = 457). All subjects in this analysis had had one or more prior pregnancies. Eighty-eight cases (41.7 per cent) and 177 controls (38.7 per cent) had a history of one or more induced abortions. The relative risk of ectopic pregnancy associated with one abortion was 0.9 (95 per cent confidence interval 0.6, 1.3), adjusted for age, county, reference date, religion, gravidity, age at first pregnancy, lifetime number of sexual partners, and miscarriage history. Among women with two or more prior pregnancies, the risk associated with two or more abortions was 1.2 (0.6, 2.4). Controlling for pelvic inflammatory disease and use of intrauterine devices did not alter these risks. We conclude that legal abortion as performed in the US since 1970 has little or no influence on a woman's risk of ectopic pregnancy in subsequent pregnancies.

Abortion, Legal↗

PubMed1979

Detection of virus antigens in Swiss albino mice infected by milk-borne mouse mammary tumour virus: the effect of age, sex and reproductive status. II. Radioimmunoassay of two virus components, gp47 and p28 in serum and organ extracts.

Extracts of various organs, mammary tumours and sera from milk-borne MMTV infected Swiss albino mice of different age, sex and physiological conditions were tested by radioimmunoassay for the presence of gp47, the main envelope polypeptide, and p28, the main core protein of the virus. Except in brain, ovaries and testes, both antigens were found in all organs of old animals and of females after the onset of their first pregnancy. Antigens were not present in organs of weanlings or in whole foetuses. Higher values were found in mammary glands, mammary tumours, epididymis and seminal vesicles. These organs also harboured a greater amount of gp47 than p28. The serum generally contained gp47 but rarely p28. This indicates that gp47 is not virion-bound in blood. Pregnancy, lactation and especially the presence of mammary tumours increased the concentration of gp47 in serum. The results do not allow localization of target organs of MMTV infection in the interval between ingestion of the virus by the suckling mouse and the first pregnancy. Moreover, results obtained with one group of mice devoid of exogenous virus show that, as endogenous MMTV genome expresses p28, it might account for part of the p28 detected exogenous MMTV-infected mice.

Aging↗

PubMed1981

Maternal sexuality during first pregnancy and after childbirth.

Information about sexual activity, enjoyment and libido was obtained at intervals from 119 primiparous women during a longitudinal survey of maternal emotional health in pregnancy and for a year after delivery. Most subjects described some reduction in the frequency of sexual intercourse and a diminution of libido and sexual enjoyment during pregnancy; this was most marked in the third trimester. After delivery, about a third of subjects had resumed intercourse by six weeks and nearly everyone had done so by three months. Nevertheless, 77% and 57% of the women were having intercourse less often at three and 12 months after delivery respectively, in comparison with the month before they became pregnant. Selected variables were examined for relationship with a low, or reduced frequency of intercourse and with a lack of enjoyment. Significant associations were found with aspects of maternal personality and childhood relationships, marital conflict, maternal depression, previous miscarriages, difficulties in conceiving and fears of harming the fetus. Nausea and vomiting during pregnancy, the mode of delivery and related obstetric and medical variables, breast-feeding and characteristics of the baby, did not appear to significantly influence maternal sexuality.

Adult↗

PubMed1995

Premature weaning in east Bhutan: only if mother is pregnant again.

The relationship between breast-feeding and subsequent pregnancy in East Bhutan is examined, against the background of local attitudes to family planning. Ninety-eight mothers who had given birth 30-36 months earlier were interviewed. Semisolid supplementary feeding was introduced at a median age of 3 months. Median total duration of breast-feeding was 28 months, and day and night breast-feeding on demand was continued throughout. Median duration of postpartum amenorrhoea was 12 months, and was associated with the timing of the introduction of supplementary foods. There was a significant association between the occurrence of a subsequent pregnancy and early termination of breast-feeding. The relationships between breast-feeding pattern and pregnancy interval are complex, and their relative influence changes with time. During the first year postpartum, infertility during lactational amenorrhoea is important. During the second year there is a strong negative effect on lactation from the next pregnancy. The only important reason for ceasing to breast-feed within 2 years seems to be a new pregnancy.

Amenorrhea↗

PubMed1982

[Copper containing intrauterine devices. Clinical and social aspects].

1032 women had their first Copper-T inserted, 204 became pregnant, had an expulsion or a removal for medical reasons (19.76%). Of 299 women with their second Copper-T only 15 reported these events (5.02%). Gross-rates show no difference for pregnancy, expulsion, removal because of bleeding or pain or for other medical reasons in different time-intervals of the first year of use, but in total lower event rates for the second year of use. The risk for pregnancy is not reduced for a woman with her second IUD (second segment). Other events and side-effects are reduced and explain the higher continuation-rate for the second segment. If the second IUD is not inserted immediately after removal of the first IUD, the event rate is again increasing.

Adult↗

PubMed1987

Menstrual and reproductive factors and the risk of myocardial infarction in women under fifty-five years of age.

The relationship between menstrual and reproductive factors and subsequent risk of coronary heart disease was investigated in a hospital-based case-control study of 202 women with acute myocardial infarction and 374 control subjects admitted for a wide spectrum of acute conditions unrelated to any of the established risk factors for ischemic heart disease. No consistent association was observed with age at menarche or menopausal status, but women with a lifelong irregular menstrual cycle pattern were at significantly elevated risk of myocardial infarction (relative risk = 1.8, 95% confidence interval = 1.1 to 2.9). No clear trend in risk was evident with the number of livebirths, miscarriages, or induced abortions. However, women whose first pregnancy or livebirth occurred before age 20 years showed elevated risks of subsequent myocardial infarction compared with nulliparous ones (relative risks = 2.3; 95% confidence interval = 1.1 to 4.9), and there was a significant trend of increasing risk with earlier first birth. These associations were evident in both younger and middle-age women and were not explained by allowance for several identified potential confounding factors.

Adult↗

PubMed2005

Circulating levels of the antiangiogenic marker sFLT-1 are increased in first versus second pregnancies.

Preeclampsia is far more common in women's first pregnancy but the mechanism of this association is unknown. Altered angiogenesis, marked by increased levels of circulating soluble fms-like tyrosine kinase (sFlt-1), an inhibitor of placental growth factor (PlGF) and vascular endothelial growth factor, has been implicated in the pathogenesis of preeclampsia. We tested the hypothesis that nulliparous women demonstrate increased sFlt-1 levels compared with multiparous women, suggesting an overall increase in relative antiangiogenesis during first pregnancies. We measured sFlt-1 and PlGF levels in early pregnancy serum samples from the first 2 completed pregnancies of 97 women who participated in the MOMS cohort study. Repeated measures analyses demonstrated that sFlt-1 levels were significantly increased in first compared with second pregnancies (877+/-598 pg/mL vs 728+/-399 pg/mL; P=.01) but there was no significant difference in PlGF levels (45.3+/-40.7 pg/mL vs 40.1+/-31.9 pg/mL; P=.14). After adjusting for age, gestational age, blood pressure, body mass index, smoking, and the interpregnancy time interval, the residual decrease in sFlt-1 levels from the first to the second pregnancy remained significant at 107 pg/mL (P=.04). Significant interaction between ethnicity and pregnancy order on sFlt-1 levels was observed such that Hispanic women demonstrated greater sFlt-1 levels than white women during their first pregnancy but lower levels in their second pregnancies. Increased sFlt-1 secretion in first versus second pregnancies may account in part for the increased risk of preeclampsia among nulliparous women. Additional studies are needed to verify these findings and to further examine ethnic differences in angiogenesis factors and their potential impact on the incidence of preeclampsia.

Adult↗

PubMed1999

Risk factor profiles of placental abruption in first and second pregnancies: heterogeneous etiologies.

The objective of this study was to identify risk factors for placental abruption in first and second pregnancies and to compare the risk-factor profiles for evidence of etiologic heterogeneity. A prospective cohort design was used. The study took place at university-based medical centers that participated in the U.S. Collaborative Perinatal Project (1959-1965). A total of 10,774 first pregnancies only and 6529 first and second pregnancies of women were enrolled in the study. Participation rate was 96%. All pregnancies were selected at some centers, whereas other centers used either random or systematic sampling. The main outcome measure was placental abruptions in first and second pregnancies. The placental abruption rate was 1.7% (n = 182) for first and 2.2% (n = 143) for second pregnancies. Prior abruption increased risk in second pregnancies significantly (odds ratio [OR] = 3.2, 95% confidence interval [CI]: 1.7-5.8) after adjusting for other risk factors. Placental infarcts and smoking duration were associated with an increased risk for abruption in second but not first pregnancies. Effect of placental infarcts was modified by gestational age with strongest risk for abruption at shortest gestations. For each year of smoking prior to pregnancy, risk of abruption increased 40% (OR = 1.4, 95% CI 1.0-1.8). Etiologies of placental abruption for first and second pregnancies were different, indicating heterogeneity in their risk-factor profiles. Future research would best consider abruption as a heterogeneous complication to further knowledge of its etiology.

Abruptio Placentae↗

PubMed2006

Previous cesarean delivery and risks of placenta previa and placental abruption.

OBJECTIVE: To examine the association between cesarean delivery and previa and abruption in subsequent pregnancies. METHODS: A retrospective cohort study of first 2 (n = 156,475) and first 3 (n = 31,102) consecutive singleton pregnancies using the 1989-1997 Missouri longitudinally linked data were performed. Relative risk (RR) was used to quantify the associations between cesarean delivery and risks of previa and abruption in subsequent pregnancies, after adjusting for several confounders. RESULTS: Rates of previa and abruption were 4.4 (n = 694) and 7.9 (n = 1,243) per 1,000 births, respectively. The pregnancy after a cesarean delivery was associated with increased risk of previa (0.63%) compared with a vaginal delivery (0.38%, RR 1.5, 95% confidence interval [CI] 1.3-1.8). Cesarean delivery in the first and second births conferred a two-fold increased risk of previa in the third pregnancy (RR 2.0, 95% CI 1.3-3.0) compared with first two vaginal deliveries. Women with a cesarean first birth were more likely to have an abruption in the second pregnancy (0.95%) compared with women who had a vaginal first birth (0.74%, RR 1.3, 95% CI 1.2-1.5). Two consecutive cesarean deliveries were associated with a 30% increased risk of abruption in the third pregnancy (RR 1.3, 95% CI 1.0-1.8). A second pregnancy within a year after a cesarean delivery was associated with increased risks of previa (RR 1.7, 95% CI 0.9-3.1) and abruption (RR 1.5, 95% CI 1.1-2.3). CONCLUSION: A cesarean first birth is associated with increased risks of previa and abruption in the second pregnancy. There is a dose-response pattern in the risk of previa, with increasing number of prior cesarean deliveries. A short interpregnancy interval is associated with increased risks of previa and abruption. LEVEL OF EVIDENCE: II-2.

Abruptio Placentae↗

PubMed1994

Outcome after maternal varicella infection in the first 20 weeks of pregnancy.

BACKGROUND: Infection with the varicella-zoster virus during pregnancy can produce an embryopathy characterized by limb hypoplasia, eye and brain damage, and skin lesions. The risk is greatest when infection occurs during the first 20 weeks of pregnancy, but the magnitude of the risk is uncertain. METHODS: We studied 106 women with clinically diagnosed varicella infection in the first 20 weeks of pregnancy and compared the outcomes with those in 106 age-matched, nonexposed controls. RESULTS: Among the women with varicella, there was a trend toward more elective terminations of pregnancy (14 percent, vs. 7.5 percent among the controls; P = 0.1), corresponding to a significantly higher perception of teratogenic risk (P = 0.03). The proportions of miscarriages and live births and the mean birth weights were similar in the two study groups; there were more premature births (< or = 37 weeks) among the women with varicella infection (14.3 percent vs. 5.6 percent, P = 0.05). Congenital defects occurred in four infants born to the women with varicella (varicella embryopathy, hydrocephalus, meningocele and clubfeet, and hammer toe) and two infants born to the controls (ventricular septal defect and hip dislocation). The risk of varicella embryopathy after infection in the first 20 weeks was 1.2 percent (95 percent confidence interval, 0 to 2.4 percent). When we pooled our results with those from other prospective studies, the mean risk of embryopathy after infection with varicella-zoster virus in the first trimester was 2.2 percent (95 percent confidence interval, 0 to 4.6 percent). CONCLUSIONS: The absolute risk of embryopathy after maternal varicella infection in the first 20 weeks of pregnancy is about 2 percent.

Chickenpox↗

PubMed1995

Some factors influencing pregnancy rate and subsequent litter size in primiparous sows.

The pregnancy rate and the subsequent litter size were studied in 332 Swedish Yorkshire primiparous sows, fed according to a commercial Swedish feeding regime during lactation. The sows were weighed and backfat depth was recorded at the first farrowing, at weaning, and at mating. Oestrous detection was performed once daily after weaning, and the interval from weaning to first oestrus (IWO) was recorded. Blood samples for determination of plasma progesterone were drawn regularly after the first weaning. Statistical analyses were only performed on sows with an IWO of 3-8 days. Of these 206 sows were mated on their first (OE1 sows) and 87 sows on their second (87 OE2 sows) oestrus after weaning. The pregnancy rate was 85.4% for OE1 sows and 75.9% for OE2 sows (p = 0.048). There was no significant difference in pregnancy rate between OE1 sows with an IWO of 3-5 days and OE1 sows with an interval of 6-8 days. OE2 sows with an IWO of 6-8 days, on the other hand, had a significantly lower pregnancy rate compared with OE2 sows with an interval of 3-5 days. The pregnancy rate in sows that lost more than 30 kg during the first lactation period did not differ from that of sows losing less than 30 kg. In sows with a first litter size of more than 9 piglets alive at birth, the pregnancy rate decreases significantly if mating is delayed until the second oestrus after weaning. OE2 sows had a significantly larger second litter size at birth than OE1 sows (+2.0). The litter size at six weeks did not, on the other hand, differ significantly (+0.4). There was a positive correlation between the IWO and 2nd litter size, although significant only for OE1 sows between the IWO and litter size alive at birth. In the OE1 group, sows losing 20 kg or less during lactation had significantly larger second litters at birth than the sows losing 21-30 kg, but not significantly larger than the sows losing more than 30 kg. One piglet more, at birth, in the first litter resulted in 0.25 piglet more in the second litter. For sows with a large first litter there was a low probability of also having a large second litter.

Animals↗

PubMed1984

A prospective study of emotional disorders in childbearing women.

A group of first-time mothers (119) were interviewed repeatedly at fixed intervals during their pregnancies and until their babies were a year old; they were then followed up at four years. A similar investigation was carried out on 38 other primiparae and 39 multiparae, but only postnatally. The incidence of depressive neurosis rose significantly in early pregnancy and in the first three months after delivery (10 per cent and 14 per cent of the main sample respectively). Subjects mainly suffered either from antenatal or postnatal depression, not both. Marital conflict and severe doubts about having the baby were associated with depression at either time. Bereavement and preterm birth were the only life events to relate with the onset of depression and bereavement had a greater impact during pregnancy. Depressed mothers were more likely to express negative or mixed feelings about their three-month-old babies. Many who had become depressed for the first time in their lives continued to experience psychological problems for up to four years after childbirth.

Adult↗

PubMed2003

Pregnancy outcome in liver transplant recipients.

OBJECTIVE: To evaluate pregnancy course, complications, and outcomes in liver transplant recipients. METHODS: We conducted a retrospective review of 38 pregnancies conceived between 1992 and 2002 in 29 women who underwent liver transplantation at Mount Sinai Medical Center. RESULTS: The most common primary liver disease was autoimmune hepatitis. All patients were on immunosuppressive regimens that included cyclosporine A or tacrolimus. There were four spontaneous first-trimester abortions and ten first-trimester terminations for worsening liver function. The interval from transplantation to pregnancy was shorter in the group that had abortions and terminations (24.4 +/- 24.3 months) as compared with the group that had live births (47.8 +/- 28.7 months), P =.02. There were 24 live births to 20 patients. The mean gestational age at delivery was 36.4 weeks, and the mean birth weight was 2762 g. Pregnancy complications included preeclampsia (20.8%), chronic hypertension (20.8%), hemolysis, elevated liver enzymes, low platelets syndrome (8.3%), creatinine 1.3 mg/dL or more (25.0%), anemia (33.3%), diabetes (37.5%), cesarean delivery (45.8%), preterm birth less than 37 weeks (29.2%), intrauterine growth restriction (16.7%), and biopsy-proven graft rejection during pregnancy (16.7%). There were no intrauterine or neonatal deaths. All 5-minute Apgar scores were greater than 7. Four minor congenital anomalies were noted. Before 1997, there were five maternal deaths, 10-54 months after pregnancy. Pregnancy complications in our population were more common in those patients who delivered from 1992 to 1997 than in those who delivered from 1998 to 2002. CONCLUSION: Pregnancy planned at least 2 years after liver transplantation with stable allograft function can have excellent maternal and neonatal outcome.

Abortion, Spontaneous↗

PubMed1996

Menstrual and reproductive factors related to the risk of breast cancer in Korea. Ovarian hormone effect on breast cancer.

To support the ovarian hormone hypothesis in the etiology of breast cancer, a hospital-based case-control study with community controls was conducted to evaluate the relationship of intervals among menstrual and reproductive events to the risk of breast cancer in Korea. The cases were 190 breast cancer patients, who had been histologically diagnosed at Seoul National University Hospital from Jan. 1, 1993 to Jun. 30, 1994. Included were cancer-free women, who had undertaken the Gynecological examination at the same hospital (n=190). Women recruited for a survey of diabetes prevalence in Yonchon County, adjacent to Seoul City, were taken as a community control group (n=190). Information on menstrual and reproductive factors with other life-styles was collected through a direct interview by the well-trained interviewers. The adjusted odds ratios and the 95% confidence intervals were based on the unconditional logistic regression model. Likelihood ratio test for trend was applied for the ordinal variables. Early age at menarche, late age at natural menopause, late age at first full term pregnancy, and fewer number of full term pregnancies are independently associated with the high risk of breast cancer in Korea. Moreover, the interval between the age at menarche and the age at natural menopause of community controls (29.9+/-6.15 years) was significantly shortened compared to breast cancer cases (34.9+/-4.42 years). Particularly noteworthy was that intervals between the age at menarche and the age at first full term pregnancy of both control groups (9.0+/-3.72 years for hospital controls; 7.2+/-4.04 years for community controls) were significantly shortened compared to breast cancer cases (11.0+/-4.51 years). These findings support the hypothesis that the longer exposure to ovarian hormones during the reproductive years, the higher the risk of breast cancer.

Adult↗

PubMed1995

Abortion and the risk of breast cancer: a case-control study in Greece.

We have examined the association between induced or spontaneous abortion and breast cancer risk in Greece. In a hospital-based case-control study in Athens, 820 patients with confirmed breast cancer were compared with 795 orthopedic patient controls and 753 healthy visitor controls, matched to cases by age and interviewer. Logistic regression was used to analyze the data, controlling for demographic, reproductive and nutritional variables. Odds ratio (OR) patterns were similar for the 2 control series, which were therefore combined to increase precision of the estimates. The risk for breast cancer was not increased for women who had a history of abortion, compared to nulliparous women with no history of abortion. Thus ORs and 95% confidence intervals were for nulliparous women with spontaneous abortion, 1.17 (0.64-2.13); for nulliparous women with induced abortion, 0.98 (0.56-1.73); for parous women with no abortion, 0.56 (0.31-1.01); for parous women with spontaneous abortion, 0.61 (0.33-1.14) and for parous women with induced abortion, 0.99 (0.56-1.74). When the analysis was restricted to parous women, using parous women with no history of abortion as the baseline, ORs and 95% confidence intervals were for induced abortion before first full-term pregnancy, 2.06 (1.45-2.90); for induced abortion after first full-term pregnancy, 1.59 (1.24-2.04) and for spontaneous abortion, 1.10 (0.82-1.40). Our findings suggest that an interrupted pregnancy does not impart the long-term protective effect of a full-term pregnancy attributable to terminal differentiation.

Abortion, Induced↗

PubMed1993

A case-control study of thyroid cancer in women under age 55 in Shanghai (People's Republic of China).

A population-based interview study of 207 case-control pairs investigated reproductive, dietary, and other factors thought likely to increase thyroid cancer risk among women of reproductive age in Shanghai. Of particular interest were factors that might help explain the striking female over male excess in this age group. Risk was strongly associated with prior goiter or benign nodules (odds ratio [OR] = 7.0, 95 percent confidence interval [CI] = 2.5-27.5) and miscarriage as outcome of first pregnancy (OR = 9.9, CI = 2.0-48.4). Weaker associations were seen for women who were ever-pregnant (OR = 2.1, CI = 1.1-4.2), ever had an induced abortion (OR = 1.6, CI = 0.9-2.9), and ever used oral contraceptives (OR = 1.7, CI = 1.0-3.1). Compared with controls, cases gained significantly more weight from menarche to highest nonpregnant weight (P trend < 0.01). Overall, cases ate more fish and shellfish, but there was no trend with level of consumption. More cases had a parent, sibling, or child with thyroid disease (OR = 5.2, CI = 2.5-12.1). Our findings relating to goiter and benign nodules and various reproductive factors support earlier studies. Consumption of seafood was difficult to evaluate; more detailed dietary data are needed to assess iodine intake.

Abortion, Spontaneous↗

PubMed1976

Serum unconjugated estriol levels in the third trimester and their relationship to gestational age.

Maternal unconjugated estriol levels were measured throughout the 28 to 41 week interval in two groups of accurately dated normal pregnancies. The first group consisted of randomly sampled pregnancies on which 285 unconjugated estriol determinations were performed. The logarithms of the mean values plotted into a positive sloping, relatively straight line which was disrupted by a plateau originating at 31 to 32 weeks and terminated at 35 weeks where there began a steep surge to a point at 36 weeks (surge point) that returned values to fit the previously established straight line. To investigate these findings in individual pregnancies, a second group of nine subjects was studied with serial unconjugated estriol determinations. In all nine of these subjects, the surge point could be identified statistically and occurred at a mean gestational age of 36.0 +/- 0.6 (1 S.D.) weeks. Data from the first group of randomly sampled pregnancies indicate that the surge point occurred around a mean gestational age of 36.0 weeks and was confirmed by data from the second group of serially sampled individual subjects showing the surge point as a statistically definable marker in normal pregnancies.

Adrenal Glands↗