Pregnant women who catch Covid are twice as likely to develop serious complications and three times more likely to suffer a potentially fatal blood clot, warns a new study. Coronavirus also doubles the risk of of premature birth, acute respiratory distress syndrome and sepsis, according to the research.
In the UK, mums-to-be who have not had the jab make up a fifth of the most ill patients in intensive care, data showed. Infected patients who took part in this latest study were three times as likely to have a blood clot - known medically as a thromboembolism, scientists discovered.
Thromboembolism can cause a blockage in the main artery of the lung or form elsewhere and become life threatening. Overall, the coronavirus raised the risk of a severe maternal illness two-and-a-half times, researchers found.
Pre-term births during early, middle, and late terms of the pregnancy doubled, while birth may need to be induced early when the mother has a condition such as pre-eclampsia, the study revealed. Dr Assiamira Ferrara, a lead author of the study at California-based care consortium Kaiser Permanente, said: "These findings add to growing evidence having Covid-19 during pregnancy raises risks of serious complications."
The findings were based on 43,886 expectant women in the US of whom 1,332 became infected. Dr Ferrara added: "Coupled with the evidence the Covid-19 vaccines are safe during pregnancy, these findings should aid patients in understanding the risks of perinatal complications and the need for vaccination. This study supports the recommendation for vaccination of pregnant individuals and those planning conception."
California-based care consortium Kaiser Permanente tracked participants from before conception to delivery to identify links between before and after birth complications. Covid was diagnosed through a PCR test by the researchers. The racially and ethnically diverse group was followed from March 2020 to March 2021.
Those who tested positive were more likely to be younger, obese, Hispanic, have had multiple babies or live in a poor neighbourhood, scientists said. Dr Mara Greenberg, a co-author of the study and a maternal-fetal medicine specialist, said: "Our study was large, diverse, and supports the need for vaccination by pregnant individuals and those who plan to get pregnant. The most important thing people can do to protect themselves and their baby is to get vaccinated."
The analysis found almost six per cent of patients with a coronavirus infection during pregnancy had a related hospitalisation. That was most likely for black or Asian or Pacific islanders and patients with pre-gestational diabetes, the study found.
Researchers compared patients who gave birth before and after December 2020, when universal Covid testing of pregnant patients began. They found a positive test rate of 1.3 and 7.8 per cent, respectively. The same health risks applied to both groups. The US team is continuing to research Covid and pregnancy, focusing on telemedicine and health care delivery during the pandemic.
Dr Monique Hedderson, another study co-author, said: "We are also planning to follow both mothers and children to study possible short and long-term health effects of coronavirus infections during pregnancy." In November analysis of 200,000 pregnant women in France found those with Covid were 40 times as likely to die during childbirth, scientists said. The study was published in JAMA Internal Medicine.