In this retrospective single center study, all men with semen analyses performed at the laboratory the Deventer Hospital between January 2003 and December 2017 were included. The Deventer Hospital is a teaching hospital in the Netherlands. Around 280 semen analyses are performed each year. Semen analysis is performed according to the current WHO guidelines, in which the SpermMAR test (FertiPro, Beernem, Belgium) is routinely performed [5]. The gynaecologist generally performed a semen analysis as part of the fertility work-up, including an ovulation assessment, a post coital test and a Chlamydia-antibody test (CAT), as well. Depending on the results of the fertility work-up and the calculated prognosis on a spontaneous pregnancy in one year, based on Hunault if applicable, couples were advised to expected management for a certain period or to start with ART [18].

To examine the influence of ASA on subfertility, a sub population was identified. In this sub population all subfertile couples who were under treatment of a gynaecologist between January 2003 and December 2017 were included if at least one sperm analysis showed the presence of an IgG and/or IgA spermMar test percentage of ≥50%. Couples were excluded when the woman had an anovulatory cycle that could not be corrected with ovulation induction, or in case of bilateral occlusion of the fallopian tubes.

The primary parameters of the study were the presence of ASA in all semen analysis during the study period and the incidence of ASA in the subfertile population.

The other parameters that were investigated were the incidence of men who had a plausible explanation for the presence of ASA, such as operations and their medical history. Furthermore, the influence of ASA on sperm parameters and fertilization, including the spontaneous pregnancy rate were measured. In addition, the type and number of ART such as IUI, in vitro fertilization (IVF) and/or Intracytoplasmic Sperm Injection (ICSI), and pregnancy outcomes were measured in the subfertile population with a positive ASA male.

The following parameters were anonymously collected from the electronic patient data system: age (at first visit at the gynaecologist), race, BMI, duration of subfertility (time between the pregnancy wish and the start of ART), duration of the pregnancy wish (time between the pregnancy wish until the onset of a pregnancy), and a history of conditions that could negatively affect fertility. The following environmental factors were noted: intoxications, medication that could have an adverse effect on fertility such as testosterone [19]. Furthermore, professions that are known to influence fertility were noted such as CO₂ welding or irregular shifts [20] [21]. Variables were excluded in case of more than 10% missing values, to avoid bias [22].

In men, sperm parameters (concentration, motility, morphology and the percentage of IgG and IgA) of all semen analyses during the study period (2003-2017) were retrieved from the data system of the laboratory. If more than one sperm analysis of a man was present, the sperm analysis with the highest percentage of IgG and IgA was used for analysis.

In women, the type and number of ART, the mode of conception, the number of pregnancies and the pregnancy outcome after ART were examined. A pregnancy was defined as a clinical pregnancy demonstrated with a pregnancy test and/or ultrasound.

Furthermore, to examine the influence of ASA on fertility, pregnancy rates after IUI between 2011 and 2017 were examined. Pregnancy rates after IVF/ICSI in the Deventer hospital between 2003 until 2016 were collected as well, since the treatments that have started in 2017 have not all been completed during the study period, yet.

Data were analyzed using SPSS Statistics for windows, version 24.0 (Armonk, NY) [23]. Descriptive statistics were presented in means and standard deviations for continuous and normally distributed variables; median and interquartile ranges for continuous non-normally distributed variables and proportions and absolute numbers for categorical variables. A Chi squared test/Fisher’s exact test as appropriate was performed on dichotomous variables. A p-value of <0.05 was considered significant.

The local medical ethics committee of the hospital obtained ethical approval (n-WMO), reference number ME-17-69, in accordance with the Declaration of Helsinki.

During the study period 4283 sperm analyses were performed, of which 28% were repeated semen analyses. After exclusion of these repeated analyses, 3098 semen analyses remained (see Figure 1). In the 3098 semen analyses, 233 analyses with positive ASA were described, resulting in an incidence of 7.5%. From the 233 ASA positive men, 182 got a fertility work-up and from the 3098 men who had semen analyses, 2229 visited the gynaecologist for a fertility work-up. Resulting in an incidence of ASA of 8.2% in the subfertile population, defined as a pregnancy failure after one year or more of regular unprotected sexual intercourse.

For the sub analyses of ASA in the subfertile population (n = 182), the couples with female subfertility were excluded (n = 7), resulting in the inclusion of 175 couples. For the other analyses, all 233 ASA positive male were included.

The mean male age was 34.8 (± 6.7) years at the start of the fertility work-up (Table 1). Ten of the 175 men were known to have a profession associated with reduced sperm quality, with CO₂ welder occurring most frequently. Eight men were known to use medication (e.g. prednisone, testosterone, paroxetine and cladribrin) that could have a negative influence on the quality or quantity of the sperm. However, none of these men had an oligoasthenoteratozoospermia (OAT) (sperm concentration of <15 × 10⁶/ml, progressive motility of <32% and less than 4% of the spermatozoa with normal morphology) or oligospermia. Six men had an existing condition or condition in the past that could have a negative effect on fertility, such as a malignancy requiring chemotherapy or a testosterone deficiency.

¹A possible negative effect on sperm parameters or fertility as described in literature; ²Sexual dysfunction or decreased libido were not present and the decreased quality of the sperm did not cause the presence of an OAT.

To identify causes of ASA, all 233 ASA positive men were analyzed. In 79 of the 233 ASA positive men a plausible cause of ASA was reported, while in 27 documentation was missing. The most common causes of ASA were a vasectomy, a vasovasostomy (n = 57) and an inguinal hernia (n = 10). Other reported causes were an operative corrected cryptorchism (n = 8), an epididymitis (n = 6), a trauma of the genital area (n = 3), an operative corrected varicocele (n = 1) and a testical carcinoma (n = 1).

No association was found between professions associated with reduced sperm parameters and the occurrence of an OAT. However, ASA positive men had significantly more often an abnormal sperm analysis defined as the presence of an OAT, oligoasthenozoospermia (OA), oligoteratozoospermia (OT), asthenoteratozoospermia (AT), oligozoospermia (O), asthenozoospermia (A) or teratozoospermia (T) compared to ASA negative men (64% vs 56%, p = 0.02). From the 233 men with positive ASA, only 85 men (36%) had no other abnormal sperm parameters. The ASA positive men with aberrant sperm analyses had significantly more frequent an OAT compared to ASA negative males (12% vs 8%, p = 0.008). In addition, significantly more ASA positive men had an asthenoteratozoospermia and an asthenozoospermia compared to ASA negative men (p = 0.004, and p = 0.02, respectively), see Table 2.

Of the 233 ASA positive men, 226 men (97%) had positive IgG ASA, and 56 (24%) positive IgA ASA. In total, 163 men were observed with only positive IgG ASA (70%), and seven men with only positive IgA (4%). Positive IgG ASA were observed in all men after a vasectomy and vaso-vasostomy. Positive IgA was only diagnosed in 27 men with a vasectomy and vaso-vasostomy.

OAT: oligoasthenoteratozoospermia, OA: oligoasthenozoospermia, OT: oligoteratozoospermia, AT: asthenoteratozoospermia, O: oligozoospermia, A: asthenozoospermia, T: teratozoospermia.

The median duration of subfertility at the first visit to the gynaecologist for a fertility work-up of the 175 couples was 16 months (IQR 12 - 24). After one year of expectant management, 104 of the 175 couples received ART consisting of IUI, IVF and/or ICSI.

Ninety of the 104 couples started an IUI treatment. From these couples, 37 continued with IVF after IUI treatment was not successful after 4 - 6 cycles and 15 couples switched to ICSI thereafter. Fourteen couples switched to ICSI after IUI because of a VCM (volume, count and motility) of less than 1 million. This VCM was determined during the semen analyses for IUI treatment.

Four of the 104 couples were primarily advised to start with IVF because of a VCM around 1 million, followed by ICSI in two of the four couples because of the absence of a pregnancy and a VCM of less than 1 million. Ten couples were directly advised ICSI because of a VCM of less than 1 million.

In total, 69 of the 175 couples (39%) get pregnant spontaneously in the year of expectant management or during the ART treatment, despite the presence of ASA (Table 3). Furthermore, in 18 couples (10%) a spontaneous pregnancy occurred, but ART treatment was needed for another pregnancy. Of the 175 couples, 27 (15%) couples became pregnant after IUI treatment, 21 (12%) after IVF treatment, 30 (17%) after ICSI treatment and 34 (19%) women did not became pregnant. The median duration between a pregnancy wish and onset of the first pregnancy was 26 months (IQR 17 - 37) ranging from 20 months in the group of spontaneous conception (IQR 14 - 31) to 36 months in the group of ICSI (IQR 25.5 - 50.5).

Pregnancy rates after ART

IUI was performed in 90 of the 175 couples. A total of 40 pregnancies occurred in 27 couples, since in some couples more than one pregnancy occurred. The pregnancy rate per IUI cycle per couple was 10%, and the total rate per couple 30%.

Forty-one of the 175 couples had one or more IVF treatments, leading to 37 pregnancies in 21 couples. The pregnancy rate per IVF cycle per couple was 36% in couples with ASA positive men, while the average pregnancy rate per cycle of all performed IVF cycles in our hospital was 30% without including cryo transfers. The pregnancy rate after IVF per couple was 46% and increased to 51% when including cryo transfers.

Forty-one of the 175 couples had one or more IVF/ICSI treatments. A total of 40 pregnancies were observed in 30 couples. The pregnancy rate per ICSI cycle was 32% in couples with ASA positive men, compared to an average pregnancy rate of 28% per cycle of all ICSI cycles performed without including cryo transfers. The total pregnancy rate after ICSI per couple was 63% and increased to 73%when including cryo transfers.

Of the 248 pregnancies that occurred, 183 ended in a live birth (74%), and 60 ended in a miscarriage <16 weeks (24%). Five pregnancies ended in a non-live birth after 16 weeks (2%). Except for two children that were born at 36 weeks of gestation (1%), all children were born at term.