A recent meta-analysis examines if D&C can lead to future premature birth. Plus, does counseling on LARCs lead to a reduction in pregnancy rates. And: does exposure to DDT while in utero mean an increased risk of breast cancer later in life?
Results of a meta-analysis presented at the annual conference of the European Society for Human Reproduction and Embryology (ESHR) suggest that dilatation and curettage (D&C) may be a risk factor for preterm birth. The findings, by Dutch investigators, point to a need to minimize D&C and use noninvasive methods of uterine evacuation when possible.
Included in the report were 21 studies reflecting data on 1.8 million women, dating from the inception of OVID MEDLINE and OVID EMBASE to May 2014. No randomized controlled comparisons were found of women with and without a history of D&C and subsequent preterm birth. The authors noted that findings from some but not all of the cohort or case control studies reviewed were corrected for confounding factors.
Nevertheless, the meta-analysis revealed odds ratios (OR) of 1.29 (95% CI 1.17; 1.42) for preterm birth, 1.69 (95% CI 1.20; 2.38) for very preterm (<37 weeks), and 1.68 (95% CI 1.47; 1.92) for <28 weeks in women with a history of D&C. The risk of preterm birth remained higher for D&C even when the control group was limited to women with a medically managed miscarriage or induced abortion (OR 1.19; 95% CI 1.10; 1.28). For women with a history of multiple D&Cs, the OR for preterm birth (<37 weeks) was 1.74 (95% CI 1.10; 2.76). Limiting the analysis to spontaneous preterm birth subsequent to D&C, the OR was 1.44 (95% CI 1.22; 1.69).
“These data,” the authors said, “warrant caution in the use of D&C for miscarriage and induced abortions. This conclusion should contribute to the implementation of misoprostol as a noninvasive treatment option for both miscarriage and induced abortion.”
Counseling about LARCs can impact pregnancy rates
A study performed at 40 reproductive health clinics across the United States underscores the influence that counseling about and access to long-acting reversible contraceptives (LARCs) can have on adoption of the devices. The results, published in The Lancet, suggest that providing staff with evidence-based training on how to counsel and insert LARCs may reduce pregnancy rates.
The research, a cluster randomized trial, was performed at the clinics from 2011 to 2013. Staff at 20 of the 40 sites were randomly assigned to receive evidence-based training on providing counseling and insertion of intrauterine devices (IUDs) or progestin implants (intervention); at the other 20, locations (controls), standard care was available to patients. At all 40 clinics, the training had no impact on the cost of provision of LARCs. For the study, women aged 18 to 25 years were recruited who were at the clinics for either family planning or abortion care visits and did not want to become pregnant in the next 12 months. The primary outcome was the selection of a LARC; pregnancy within 12 months was the secondary outcome.
Overall, 1500 women were enrolled. More women reported receiving counseling on IUDs or implants at the clinics where training had been undertaken than at the control sites (565 of 797 vs 271 of 693, odds ratio 3.8, 95% confidence interval [CI] 2.8 – 5.2). In addition, LARC was chosen by more women seen at the intervention clinics than at the control locations (224 vs 117, odds ratio 1.9, 95% CI 1.3–2.8). In the intervention group, the pregnancy rate was lower after family planning visits (7.9 vs 15.4 per 100 person-years) but not after abortion care visits (26.5 vs 22.3 per 100 person-years). Investigators discovered that the intervention-evidence-based training-had a significant effect on pregnancy rates among women who were attending family planning visits (hazard ratio 0.54, 95% CI 0.34–0.85).
The investigators concluded that offering counseling on LARCs and providing access to such devices during family planning counselling visits can reduce pregnancy rates.
In utero DDT exposure may increase breast cancer risk
Women whose mothers were exposed to dichlorodiphenyltrichloroethane (DDT) while pregnant may be at increased risk of developing breast cancer later in life, according to results of a new nested case-control study. The findings-which suggest as much as a 4-fold elevation in risk in a population born at the height of DDT use in the United States-held true regardless of maternal history of breast cancer, say the authors.
Published in The Journal of Clinical Endocrinology & Metabolism, the prospective research was based on analysis of data from 9300 daughters in the Child Health and Development Studies pregnancy cohort. The cohort comprised women who were Kaiser Foundation Health Plan members and received obstetric care in Alameda County, California between 1959 and 1967, as well as their adult daughters. A breast cancer diagnosis by age 52 years, as of 2012, was the main measured outcome.
Overall in the cohort, 118 breast cancer cases were diagnosed by age 52 years, each of which was matched to 3 controls according to birth year and trimester of maternal blood draw. Through the pregnancies studied, blood specimens were taken periodically and 1 to 3 days after delivery. In addition to DDT exposure, the authors also looked at variables such as maternal lipids, age, race, and history of breast cancer and breastfeeding.
Elevation in maternal serum levels of DDT significantly predicted a nearly 4-fold increase in a daughter’s breast cancer (odds ratio fourth quartile vs first 3.7, 95% confidence interval 1.5–9.0). The results were not confounded by maternal lipids, weight, race, age, and breast cancer history. Exposure to the pesticide, the authors said, was “significantly, positively associated with advanced stage at diagnosis and with the occurrence of HER2-positive tumors.”
The researchers did point out that their study only investigated breast cancer diagnosed before age 52 years and further follow-up is needed to confirm their findings and identify causal mechanisms. They believe, nevertheless, that their data support classifying DDT as a predictor of breast cancer, a marker of high risk, and an endocrine disruptor.