Changes in preterm birth and stillbirth during COVID-19 lockdowns in 26 countries.
Calvert C., Brockway MM., Zoega H., Miller JE., Been JV., Amegah AK., Racine-Poon A., Oskoui SE., Abok II., Aghaeepour N., Akwaowo CD., Alshaikh BN., Ayede AI., Bacchini F., Barekatain B., Barnes R., Bebak K., Berard A., Bhutta ZA., Brook JR., Bryan LR., Cajachagua-Torres KN., Campbell-Yeo M., Chu D-T., Connor KL., Cornette L., Cortés S., Daly M., Debauche C., Dedeke IOF., Einarsdóttir K., Engjom H., Estrada-Gutierrez G., Fantasia I., Fiorentino NM., Franklin M., Fraser A., Gachuno OW., Gallo LA., Gissler M., Håberg SE., Habibelahi A., Häggström J., Hookham L., Hui L., Huicho L., Hunter KJ., Huq S., Kc A., Kadambari S., Kelishadi R., Khalili N., Kippen J., Le Doare K., Llorca J., Magee LA., Magnus MC., Man KKC., Mburugu PM., Mediratta RP., Morris AD., Muhajarine N., Mulholland RH., Bonnard LN., Nakibuuka V., Nassar N., Nyadanu SD., Oakley L., Oladokun A., Olayemi OO., Olutekunbi OA., Oluwafemi RO., Ogunkunle TO., Orton C., Örtqvist AK., Ouma J., Oyapero O., Palmer KR., Pedersen LH., Pereira G., Pereyra I., Philip RK., Pruski D., Przybylski M., Quezada-Pinedo HG., Regan AK., Rhoda NR., Rihs TA., Riley T., Rocha TAH., Rolnik DL., Saner C., Schneuer FJ., Souter VL., Stephansson O., Sun S., Swift EM., Szabó M., Temmerman M., Tooke L., Urquia ML., von Dadelszen P., Wellenius GA., Whitehead C., Wong ICK., Wood R., Wróblewska-Seniuk K., Yeboah-Antwi K., Yilgwan CS., Zawiejska A., Sheikh A., Rodriguez N., Burgner D., Stock SJ., Azad MB.
Preterm birth (PTB) is the leading cause of infant mortality worldwide. Changes in PTB rates, ranging from -90% to +30%, were reported in many countries following early COVID-19 pandemic response measures ('lockdowns'). It is unclear whether this variation reflects real differences in lockdown impacts, or perhaps differences in stillbirth rates and/or study designs. Here we present interrupted time series and meta-analyses using harmonized data from 52 million births in 26 countries, 18 of which had representative population-based data, with overall PTB rates ranging from 6% to 12% and stillbirth ranging from 2.5 to 10.5 per 1,000 births. We show small reductions in PTB in the first (odds ratio 0.96, 95% confidence interval 0.95-0.98, P value <0.0001), second (0.96, 0.92-0.99, 0.03) and third (0.97, 0.94-1.00, 0.09) months of lockdown, but not in the fourth month of lockdown (0.99, 0.96-1.01, 0.34), although there were some between-country differences after the first month. For high-income countries in this study, we did not observe an association between lockdown and stillbirths in the second (1.00, 0.88-1.14, 0.98), third (0.99, 0.88-1.12, 0.89) and fourth (1.01, 0.87-1.18, 0.86) months of lockdown, although we have imprecise estimates due to stillbirths being a relatively rare event. We did, however, find evidence of increased risk of stillbirth in the first month of lockdown in high-income countries (1.14, 1.02-1.29, 0.02) and, in Brazil, we found evidence for an association between lockdown and stillbirth in the second (1.09, 1.03-1.15, 0.002), third (1.10, 1.03-1.17, 0.003) and fourth (1.12, 1.05-1.19, <0.001) months of lockdown. With an estimated 14.8 million PTB annually worldwide, the modest reductions observed during early pandemic lockdowns translate into large numbers of PTB averted globally and warrant further research into causal pathways.