Premature Birth and Stillbirth Rates in Germany During the COVID-19 Pandemic of 2020 and 2021

An Analysis of Epidemiological Trends

An analysis of the rates of stillbirths and premature births from 26 countries during the COVID-19 pandemic (1) did not include data from Germany, because at that time, only individual regional analyses had been published (2, 3).

Methods

We analyzed data from the nationwide German Perinatal Data Survey 2016–2021, which was made available by the Institute for Quality Assurance and Transparency in Healthcare (IQTIG). On the basis of 4,614,664 births, we studied the prevalence of stillbirths, premature births before 29 weeks’ gestation, births before 37 weeks’ gestation, or low birth weight <1500 g before and during the pandemic period 2020–2021.

Our statistical analyses comprised between-group comparisons by using χ² and t tests as well as odds ratios calculated in R (version 4.1.2). The total period 2016–2019 was compared with 2020 and 2021. Periods of “hard lockdown”—for example, with closure of public institutions—and “light lockdown”—with fewer restrictions on contact—were studied separately. To consider longer term trends in the stillbirth rate and birth numbers we predicted these for 2020 and 2021 by using time series forecasting by means of KNN (K nearest neighbor) regression.

Results

The longer term fall in the birth numbers continued in 2020 (Table); the predicted and actual numbers of about 755 000 in 2020 did not differ (p=0.77). In 2021 the actual number was 771 222, which exceeded the prediction of 740 000 (p<0.01).

Table

Trends in the prevalence of babies born with a low birth weight, premature births, and stillbirths

The rate of extremely premature births <29 weeks’ gestation remained unchanged during the pandemic period 2020–2021 compared with the years 2016–2019, at 0.72% of all births (Table). Regarding the degrees of lockdown, the prevalence of premature births <29 weeks’ gestation was lower only during the hard lockdown period in 2021 (0.65 versus 0.71%; OR 0.92; 95% confidence interval (95% CI) [0.86; 0.99]). Simultaneously, the prevalence of premature births <37 weeks’ gestation fell from 8.37% before the pandemic to 7.92% during the entire pandemic period (2020: OR 0.95; 95% CI [0.94; 0.96]; 2021: OR 0.94; 95% CI [0.93; 0.94]). It made no difference whether time periods within or outside lockdown periods were studied.

The prevalence of low birth weight fell in the years 2020 (1.34%; OR 0.96; 95% CI [0.96; 0.98]) and 2021 (1.32%; OR 0.94 [0.92; 0.96]) compared with 2016–2019 (mean) 1.41% (Table). In the periods of light lockdown 2020–2021 this fall was, however, not observed (2020: OR 0.96 [0.9; 1.02]; 2021: OR 0.96 [0.88; 1.05]).

The trend of rising rates of stillbirths described earlier (4) was confirmed (Figure, Table). In 2020 the predicted prevalence rates did not differ from the actual rates (0.39% versus 0.39%; p=0.22); the same was the case for 2021 2021 (0.43% versus 0.42%, p=0.65). By contrast, the rate of stillbirths fell during the hard lockdown in 2021 (predicted 0.44%, actual 0.38%, p<0.01).

Figure

Trend in the rate of stillbirths comparing the pre-pandemic years 2016–2019 (grey) with the pandemic period 2020–2021 (red) while considering periods of lockdown (blue-yellow underlay)

Discussion

The present analysis of data from the German Perinatal Data Survey shows comparable results to analyses from other high-income countries. Calvert et al reported a decline in the general probability of stillbirth of some 4% (OR 0.96 [0.94; 0.98]), but not in the number of extremely premature births. Furthermore, a global analysis described a pooled increase in the probability of stillbirth in the first month of a lockdown (OR 1.14 [1.02; 1.29]), which was, however, primarily explained by data from one country (Canada). In countries that are comparable to Germany—for example, Switzerland—no association with the stillbirth rate was observed (OR 1.02 [0.67; 1.55]) (1). With a different methodology and data set, Kniffka et al. were unable to model either an increase or a decrease in the stillbirth rate in the first six months of 2020 for Germany (4).

By contrast, the population in the German prospective registry study CRONOS showed in pregnant women who were symptomatically infected with SARS-CoV-2 almost double the rate of premature births in Germany, from about 9% to 17.8% (<32 weeks’ gestation: 3.3%) as well as four times the rate of stillbirths, from about 0.4% to 1.8% (5). The overall lower rate of premature births during the pandemic indicated—in spite of the SARS-CoV-2 associated premature births—pandemic-related protective changes in living circumstances for pregnant women. The containment measures with their biopsychosocial, economic, and ecologic secondary consequences may have contributed to this, combined with a possible increased vigilance vis-à-vis infections and adapted risk behavior. In spite of potential transient uncertainties and restrictions in the medical care for pregnant women during the pandemic, the rate of premature births does not seem to have been negatively affected.

Conclusions

The differentiated analysis of pandemic related changes—for example, restricted contacts and/or lower exposure of pregnant women to harmful environmental influences—can provide important pointers for possible general prevention of premature birth, on the background of the observed fall in the rate of premature births. In the face of rising numbers of infection with the current SARS-CoV-2 variant EG.5 with potential renewed restrictive containment measures, however, it is of crucial importance to maintain easily accessible prenatal care and emergency consultations for pregnant women and to communicate actively.

Yvonne Heimann, Ekkehard Schleußner, Janine Zöllkau

Jena University Hospital, Department of Obstetrics, Jena (Heimann, Schleußner, Zöllkau), [e-mail]

Conflict of interest statement
ES was the president of the German Society of Perinatal Medicine DGPM. YH and JZ declare that co conflict of interest exists.

Manuscript received on 2 September 2023, revised version accepted on 9 January 2024.

Translated from the original German by Birte Twisselmann, PhD.

Cite this as:
Heimann Y, Schleußner E, Zöllkau J: Premature birth and stillbirth rates in Germany during the COVID-19 pandemic of 2020 and 2021—an analysis of epidemiological trends. Dtsch Arztebl Int 2024; 121: 196–7. DOI: 10.3238/arztebl.m2024.0002

References

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3. David M, Reutter T: Fewer preterm births in the first COVID-19 pandemic year? An evaluation of the Berlin perinatal data for the years 2017 to 2020. Geburtshilfe Frauenheilkd 2023; 83: 184–91

4. Kniffka MS, Nitsche N, Rau R, Kühn M: Stillbirths in Germany: on the rise, but no additional increases during the first COVID-19 lockdown. Int J Gynaecol Obstet 2021; 155: 483–9

5. Iannaccone A, Mand N, Schmidt B, et al.: Is the risk of still and preterm birth affected by the timing of symptomatic SARS-CoV-2 infection during pregnancy? Data from the COVID-19 related obstetrics and neonatal outcome study network, Germany. Am J Obstet Gynecol 2023; 228: 351–352.e2