INTRODUCTION

Fertility is a demographic variable that facilitates the analysis of the growth trend of any population ^{( 1}. In the last decades, the fertility rate has decreased considerably in all regions of the world ². Latin America is one of the regions where the decline has been greater ². In Peru, between 1986 and 2017, the fertility rate decreased by 44% ³. Despite the decline, there is still a gap between desired and observed fertility, which is described as unwanted additional fertility (UAF) ⁴. This indicator varies between developed and developing countries, and between urban and rural populations. In developed countries, desired fertility is higher than observed fertility, while in developing countries, it is the opposite ^{5 , 6}.

Family planning is one of the factors associated with UAF ⁷. Although this measure has shown to be effective in controlling population growth, only 18% of people talk to their doctor about this subject and the lack of information is similar for both genders ⁸. Likewise, the use of modern contraceptive methods has not varied significantly, and the use of traditional or folkloric contraceptive methods predominates in rural areas ^{3 , 9}.

Similarly, women’s education is an important factor ¹⁰. Amaranta et al. reported that at lower education levels, observed fertility is higher than desired fertility ⁶. Regarding employment, a retrospective study conducted in the United States between 1976 and 2010 states that for every 1 percentage point increase in the unemployment rate, the fertility rate decreases by 0.5 conceptions per 1,000 women ^{( 11}.

Sexual violence is also an important factor to consider. A study of sexually abused women under 53 years of age reported increased frequency of abortion and infertility ¹². It has also been observed that intimate partner violence is associated with miscarriages, fetal death, and maternal health complications ¹³.

In short, fertility is a demographic variable that has a great impact on the country’s economic and socio-cultural development. It is postulated that decrease in a country’s fertility rate, increases the educational level of women and, with it, economic growth ¹⁴. In Peru, no data was identified that demonstrated an association between the previously described factors and the gap between observed and desired fertility. Therefore, the aim of this study is to determine the sociodemographic and reproductive factors associated with UAF in Peru.

MATERIALS AND METHODS

RESULTS

The 2018 DHS included 34,996 women between the ages of 15 and 49. Of these, 28,052 women under 40 years old were excluded because they were yet to achieve their desired fertility. Thus, 6,944 women between 40 and 49 years old were included, with an average age of 44.3 years (SD: 2.51). Sixty percent lived on the coast; 82.4% lived in the urban area; 90% had a long-term partner; 70.9% had at least a secondary school education; and 37.2% worked as professionals or in the service sector. We also found that 45.1% had a partner with secondary school education; and 33.9% had a partner with higher education. Only 24% had health insurance (Table 1). Thirty percent were married before 19 years old and 62.5% said that both members of the couple wanted the same number of children (Table 2).

The UAF prevalence was 72.5% (95% CI: 70.4%- 74.4%). The UAF rate was higher in Huancavelica (88%), Cusco (86.5%) and Madre de Dios (84.9%); and lower in Ica (64.1%), Callao (65%) and Tumbes (66.5%) (Figure 1). Of the group of women surveyed, 60.4% lived on the coast and 79.6% in the urban area; 93.7% had a long-term partner; 66.9% had at least secondary school education; and 34.9% worked as professionals or in the service sector. Only 22.9% had health insurance; 47.2% had a partner with secondary education and 30.2% with a partner with higher education. Statistically significant associations were found between UAF and area of residence, socioeconomic level, marital status, education level, occupation, education level of the partner, and health insurance coverage (Table 1).

Figure 1 Map of Peru according to the prevalence of unwanted additional fertility by region. 

From the total of women surveyed, 33.9% were married before the age of 19, 61.1% reported that both partners wanted the same number of children, 89.9% reported using modern contraceptive methods and 69.8% reported that the decision to take contraceptive methods was made jointly with their partner.

Statistically significant associations were found between age at first marriage, age at first intercourse, age at first delivery, use of anti-conceptive methods, and UAF (Table 2).

In the multiple regression model, we found that being in the upper wealth quintile decreases the probability of UAF by 20% (RPa 0.80; 95% CI: 0.69-0.93) with respect to the intermediate quintile. On the other hand, being from a rural setting increases by 7% the probability of UAF (PRa 1.07; 95% CI: 1.01-1.14) with respect to the urban setting. In addition, the fact that the respondent is the sole decision maker about her contraceptive methods increases the probability of UAF (PRa 1.10; 95% CI: 1.02-1.18) by 10% compared to having the decision made jointly with her partner. Similarly, having the interviewee and a person, other than her partner, make health decisions increases the probability of UAF by 45% (PRa 1.45; 95% CI 1.30-1.62), compared to having the decision made jointly with her partner (Table 3).

DISCUSSION

This study found high prevalence of UAF in Peruvian women aged 40-49 in seven out of every ten respondents. This finding is particularly important in those less advantaged socioeconomic sectors. A national study found that poorer populations had higher fertility and lower contraceptive use rates than wealthier populations. In Peru, only 34% of women of reproductive age in the lower socioeconomic strata use effective contraception ¹⁷. Similarly, a study in Bolivia identified that ethnic minority women had higher fertility rates than non-minority women, and this difference was almost entirely attributed to UAF in ethnic minority women ¹⁸. Thus, identifying the groups with the highest UAF is essential for reorienting family planning programs.

Similarly, the gap between desired and observed fertility, which is measured in our study as UAF, is an indicator of dissatisfaction with the reproductive ideal ¹⁹. In this sense, it has been proposed that awareness measures aimed at reducing desired family size are necessary but not sufficient to achieve a significant reduction in observed fertility. This requires expanding the system of reproductive control services, especially in vulnerable regions, after raising awareness about the importance of reducing desired fertility ^{20 , 21}. In this regard, our study identified the regions of Huancavelica, Puno, and Cusco as those with the highest UAF.

Also, our study found that women from the top wealth quintile are 20% less likely to have more children than those in the middle quintile. A study that evaluated factors associated with fertility decline in working Peruvian women found that both dependent and independent workers with high wealth are 60% less likely to have children ²². The differences in the figures cited can be explained by the different populations studied. Our study analyzed women from 40 to 49 years old, while the cited study analyzed working women of childbearing age. Another difference is the selection of the dependent variable since, in the cited study, it was the probability of having children. However, a study carried out in Brazil on women from 15 to 49 years old found similar figures to those of our study regarding the level of wealth. The top wealth quintile was reported to be 26% less likely to have more children ²³.

A higher probability of UAF was found in women working in handcraft and agriculture. Our results are consistent with previous studies in Latin America, which were collected in a systematic review ²⁴ and describe negative or non-significant associations between traditional jobs and fertility. The same study also describes a lower impact on fertility in women in independent jobs than those in dependent jobs. Therefore, we suggest exploring the contradiction between the reduced access to health services and schooling in the rural setting (where most agricultural work occurs, and which is mostly independent) and the apparent decline in fertility. Another study aimed at sociocultural differences of African women found important differences in how social context influences the impact of work on fertility, such that certain variables that positively impact fertility decrease it in other contexts, even when both are adjusted to the same variables. That study described a negative impact of female labor on fertility in the Togolese society, where there is an important syncretism between Christianity and animism; these is a similar situation to that of Peru, and that coincides with our results ^{25 , 26}.

Our study reported that if women’s health decisions are made jointly with a person other than their partners, UAF increases. A study in Bangladesh described that when decisions at home were made by a person other than the woman, the partner, or the couple, the likelihood of using contraception decreased by up to 40%. An association was also described between discordance among the responses of both partners and women’s use of contraception. To explain this behavior, the authors recommend further study of Peruvian family dynamics.

Regarding the use of contraceptive methods, the results obtained are incongruent with a previous study that evidenced family planning as a protective factor for UAF ²⁸. The authors attribute this inconsistency to the fact that the DHS asks about lifetime use of contraceptive methods, and it is possible that these methods were used at the time of the survey but were not used at the time of conception. Also, our study found that if women are the sole decision-makers about their contraceptive methods, the likelihood of UAF increases. In the literature review, no information was found about the association between the identity of who chooses the contraceptive method and fertility. However, it has been described that, despite the increased frequency of contraceptive use in Peru, especially the male condom, fertility has not been impacted as would be expected ²⁹. The authors attribute this to incorrect or inconsistent use of contraceptive methods among women who use them.

An important limitation of our study is that UAF reflects results that can only be extrapolated to populations with similar characteristics to the Peruvian one. Also, UAF is the result of family planning policies of previous years, so UAF in young women should be evaluated according to current family planning programs, whose results will be seen in the coming years.

There may also be a memory bias, as the DHS asks “have you ever ...” questions. Furthermore, because it is a cross-sectional study, it is not possible to determine a causal relationship. On the other hand, among the strengths of this study, it is worth noting that sociodemographic variables and those of the reproductive environment, both of the woman and of the partner, were analyzed. It should be noted that the sampling used by the 2018 DHS means that the results found can be extrapolated to the reality of the Peruvian female population aged 40-49.

The prevalence of UAF among Peruvian women aged 40-49 who responded to the DHS 2018 is high. We describe significant associations with socio-demographic and reproductive factors, as well as with the characteristics of women and people in their immediate environment. Due to the limitations faced during the execution of this study, we recommend conducting prospective studies that evaluate the impact of these factors on UAF in women from the first sexual intercourse onwards. We also suggest a qualitative study to evaluate the interests and opinions of this population.