To test whether subfertile women may be at higher risk of preterm delivery.
Methods
We used data from two population-based cohort studies on risk factors and pregnancy outcome for approximately 20,000 deliveries in three major Danish obstetric departments. The Aalborg-Odense study comprised all pregnant women attending routine antenatal care at two obstetric departments from 1984 to 1987. In all, 11,850 women (86%) filled in a questionnaire at about 36 weeks' gestation. The Aarhus study addressed women at the routine visit near 16 weeks' gestation from 1989 to 1991; a study questionnaire was returned by 6857 (80%). Both studies excluded women with chronic illnesses, multiple fetuses, and inability to speak Danish. Only women with planned pregnancies were included in the analysis. In all, 8855 and 3985 women from Aalborg-Odense and Aarhus, respectively, were eligible for the analyses. In both cohorts, women were categorized according to their waiting time to pregnancy (0-6 months, 7-12 months, and greater than 1 year) and according to examination or treatment for infertility (yes, no). Preterm delivery was defined as birth before 37 completed weeks.
Results
Compared with women who tried for 6 months or less before they conceived, women who tried for 7-12 months had 1.3 times (95% confidence interval [CI] 0.8, 2.1) the adjusted risk of preterm delivery in both cohorts, and women with a time to pregnancy of greater than 12 months had adjusted relative risks for preterm delivery of 1.6 (95% CI 1.1, 2.2) for Aalborg-Odense and 1.7 (95% CI 1.1, 2.6) for Aarhus. The results remained similar after excluding women with infertility treatment.
Conclusions
Pregnant women with subfertility and clinically defined infertility are more prone to preterm delivery, even in the absence of infertility treatment.
time to pregnancy preterm delivery risk subfertility, subfertility association preterm birth population cohort study, waiting time to conception preterm delivery risk factor, Henriksen Baird Wilcox subfertility preterm birth, Danish cohort study infertility pregnancy outcome, time to pregnancy greater than 12 months preterm risk, subfertile women preterm delivery without infertility treatment, population-based cohort study fecundability preterm birth, planned pregnancy waiting time adverse birth outcomes, normogonadotropic infertility spontaneous conception preterm delivery
PMID 9083319 9083319 DOI 10.1016/s0029-7844(97)00045-8 10.1016/s0029-7844(97)00045-8
Cite this article
Henriksen, T. B., Baird, D. D., Olsen, J., Hedegaard, M., Secher, N. J., & Wilcox, A. J. (1997). Time to pregnancy and preterm delivery. Obstetrics and gynecology, 89(4), 594-599. https://doi.org/10.1016/s0029-7844(97)00045-8
Henriksen TB, Baird DD, Olsen J, Hedegaard M, Secher NJ, Wilcox AJ. Time to pregnancy and preterm delivery. Obstet Gynecol. 1997;89(4):594-599. doi:10.1016/s0029-7844(97)00045-8
Henriksen, T. B., et al. "Time to pregnancy and preterm delivery." Obstetrics and gynecology, vol. 89, no. 4, 1997, pp. 594-599.
Maternal b-HCG levels fell to undetectable levels one month after birth without treatment. She was doing well and a follow-up six months later revealed no evidence of retained tissue or recurrence.
To review the evidence of effectiveness of prenatal care for preventing low birth weight (LBW). We reviewed original research, systematic reviews, meta-analyses and commentaries for evidence of effectiveness of the three core components of prenatal care--risk assessment, health promotion and medical and psychosocial interventions--for preventing preterm birth and intrauterine growth restriction (IUGR). Clinical risk assessment will fail to identify the majority of pregnancies at risk for preterm delivery or IUGR. While biophysical and biochemical modalities appear promising, their cost-effectiveness has not been demonstrated, nor can their routine use be recommended in the absence of effective interventions. Smoking cessation programs appear to be modestly effective. There is insufficient evidence to conclude a benefit for nutrition interventions, work counseling or preterm birth education. Only antenatal corticosteroid therapy has demonstrated a clear benefit in the tertiary prevention of preterm delivery. Interventions for which there is insufficient evidence to conclude a benefit include bed rest, hydration, sedation, cerclage, progesterone supplementation, antibiotic treatment, tocolysis without concomitant use of corticosteroids, thyrotropin-releasing hormone, psychosocial support and home visitation. Additionally, there is a paucity of evidence supporting the effectiveness of prenatal interventions, such as low-dose aspirin, bed rest, maternal hyperoxygenation, plasma volume expansion and antenatal fetal assessment, in preventing IUGR or its associated morbidity and mortality. Neither preterm birth nor IUGR can be effectively prevented by prenatal care in its present form. Preventing LBW will require reconceptualization of prenatal care as part of a longitudinally and contextually integrated strategy to promote optimal development of women's reproductive health not only during pregnancy, but over the life course.
The World Health Organization defines preterm birth as birth at less than 37 completed gestational weeks, but most studies have focused on very preterm infants (birth at <32 weeks) because of their high risk of mortality and serious morbidity. However, infants born at 32 through 36 weeks are more common and their public health impact has not been well studied. To assess the quantitative contribution of mild (birth at 34-36 gestational weeks) and moderate (birth at 32-33 gestational weeks) preterm birth to infant mortality. DESIGN, SETTING, Population-based cohort study using linked singleton live birth-infant death cohort files for US birth cohorts for 1985 and 1995 and Canadian birth cohorts (excluding Ontario) for 1985-1987 and 1992-1994. Relative risks (RRs) and etiologic fractions (EFs) for overall and cause-specific early neonatal (age 0-6 days), late neonatal (age 7-27 days), postneonatal (age 28-364 days), and total infant death among mild and moderate preterm births vs term births (at >/=37 gestational weeks). Relative risks for infant death from all causes among singletons born at 32 through 33 gestational weeks were 6.6 (95% confidence interval [CI], 6.1-7.0) in the United States in 1995 and 15.2 (95% CI, 13.2-17.5) in Canada in 1992-1994; among singletons born at 34 through 36 gestational weeks, the RRs were 2.9 (95% CI, 2.8-3.0) and 4.5 (95% CI, 4.0-5.0), respectively. Corresponding EFs were 3.2% and 4.8%, respectively, at 32 through 33 gestational weeks and 6.3% and 8.0%, respectively, at 34 through 36 gestational weeks; the sum of the EFs for births at 32 through 33 and 34 through 36 gestational weeks exceeded those for births at 28 through 31 gestational weeks. Substantial RRs were observed overall for the neonatal (eg, for early neonatal deaths, 14.6 and 33.0 for US and Canadian infants, respectively, born at 32-33 gestational weeks; EFs, 3.6% and and 6. 2% for US and Canadian infants, respectively) and postneonatal (RRs, 2.1-3.8 and 3.0-7.0 for US and Canadian infants, respectively, born at 32-36 gestational weeks; EFs, 2.7%-5.8% and 3.0%-7.0% for the same groups, respectively) periods and for death due to asphyxia, infection, sudden infant death syndrome, and external causes. Except for a reduction in the RR and EF for neonatal mortality due to infection, the patterns have changed little since 1985 in either country. Mild- and moderate-preterm birth infants are at high RR for death during infancy and are responsible for an important fraction of infant deaths. JAMA. 2000;284:843-849
EndometriosisFertility OutcomesEndometriosis Surgery ClaimsReproductive Treatment Access
For many patients with endometriosis, laparoscopic surgery is the most effective treatment to alleviate severe chronic pelvic pain and improve quality of life. Because endometriosis is common among individuals with infertility, surgery is often considered alongside fertility evaluation and treatment to manage symptoms, identify disease pathology, and restore pelvic anatomy. In patients who desire pregnancy, the decision of whether and when to pursue surgery should be guided by clear medical indications and shared decision making between the patient and their obstetrician-gynecologist. In recent months, however, religious and political groups have sought to reframe this medical decision as an ideologic and moral one, advocating for endometriosis surgery in nearly all patients with infertility and claiming that this can eliminate the need for assisted reproductive technologies. This framework, known as restorative reproductive medicine (RRM), aligns with efforts to promote the "personhood" of fertilized eggs, restrict access to in in vitro fertilization (IVF), and advance endometriosis surgery and lifestyle modifications as "root-cause treatment leading to natural fertility." Recent editorials and issue briefs in the obstetrics and gynecology literature have discussed the serious ethical, medical, and policy implications of RRM, yet there remains an urgent need to address specifically the unfounded claims about endometriosis surgery and its purported advantages over assisted reproductive technology. This article examines the social context of this controversy and reviews the current evidence regarding the indications, benefits, and limitations of endometriosis surgery in the management of infertility. In contrast to RRM's assertions, no evidence supports the adoption of endometriosis surgery as a replacement for IVF or as a primary treatment for infertility. Rather, the role of surgery in fertility care is highly nuanced and depends on each patient's clinical presentation, reproductive goals, and personal priorities.