OBJECTIVE: To estimate the impact of sexual behavior on the risk of recurrent @entity600 at less than 37 weeks of gestation. METHODS: This is a secondary analysis of a multicenter, blinded observational study of endovaginal sonographic examinations performed at 16-18 weeks of gestation on 187 @entity1 with singleton gestations who were at high risk for recurrent @entity600 (prior @entity600 at < 32 weeks of gestation). At the time of enrollment, each @entity1 was interviewed by a research nurse with regard to her sexual history. The @entity1 was asked about the number of sexual partners in her lifetime, the number of sexual partners since the start of her pregnancy, and, on average, the frequency of intercourse per week in the preceding month. RESULTS: A total of 165 pregnancies were available for this analysis. The population incidence of @entity600 at less than 37 weeks of gestation in the study pregnancy was 36%. An increasing number of sexual partners in a @entity1 's lifetime was associated with an increased risk of spontaneous @entity3152 (one partner 19%, 2-3 partners 29%, >or= 4 partners 44%, P = .007), whereas the number of sexual partners since the start of pregnancy was not (P = .42). @entity1 who reported infrequent sexual intercourse during early pregnancy had an incidence of recurrent @entity600 of 28% compared with 38% in those @entity1 who reported some intercourse (P = .35). CONCLUSION: Self-reported coitus during early pregnancy was not associated with an increased risk of recurrent @entity3152 . There was an association between increasing number of sexual partners in a @entity1 's lifetime and recurrent @entity3152 . LEVEL OF EVIDENCE: II-2.

Effect of coitus on recurrent XXXX .

@entity1 :: ('9606', 'Species') :: ['women', 'woman', 'patient', 'Women'] @entity3152 :: ('MESH:D007752', 'Disease') :: ['preterm delivery'] @entity600 :: ('MESH:D000014', 'Disease') :: ['spontaneous preterm birth']
@entity600 :: (MESH:D000014,Disease) :: ['preterm birth']
