Bleeding During A First Pregnancy

Women who bleed during early pregnancy without miscarrying seem to be at an increased risk for later complications of pregnancy. But the risk doesn't stop there. Bleeding during the first trimester of a first pregnancy indicates a woman may have complications with future pregnancies as well. This is according to a new study from Denmark of significant scale.

Past History

The findings of the Danish team suggest that physicians should monitor well their pregnant patients with a past history for vaginal bleeding in the first trimester. So says Dr. Jakob Alexander Lykke who is with the Roskilde Hospital.

Half of all women with first-trimester bleeding will miscarry by their 20th week of pregnancy. Those women who bleed but manage to avoid having a miscarriage are still more likely to experience pregnancy complications. In this new study, researchers attempted to establish whether the risk may be one that persists into a woman's future pregnancies.

To that end, the research team analyzed the records of almost 800,000 women who birthed a first baby between the years 1978-2007, plus a subset of 540,000 of them who had an additional child during this same time period. An approximate 2% of women from both of these groups experienced first-trimester vaginal bleeding. Of the women who bled during their first pregnancies, 6% had a premature delivery at between 32-36 weeks' gestation, in comparison to only 4% of the women who did not experience vaginal bleeding. To be considered term, a baby must be born at 37 weeks or later.

More Common

Women who delivered even earlier, at 28-31 weeks were more prevalent among the women who had experienced vaginal bleeding (0.3% compared to 0.9%). Placental abruption, in which the placenta comes away from the uterus before delivery is complete, was also more common in the women who bled (1.0% compared to 14%).

Premature rupturing of the membranes (water breaks before the 37th week) occurred in 6% of those with first-trimester bleeding and in 5% of those who did not bleed.

The researchers found that the women who bled during the early weeks of a first pregnancy but not during their second pregnancies still had a higher risk for future preterm delivery and premature rupturing of the membranes should there be a subsequent pregnancy: 8.2% delivered between 32-36 weeks compared to 2.2% of those who hadn't bled. The risk for preterm delivery stood at 4.8% and 2.7%, respectively.

Premature Rupture

Premature rupturing of the membranes in a second pregnancy after a first pregnancy with first-trimester bleeding occurred in 4% of the women compared to 3% of those women who hadn't experienced any such bleeding the first time around.