Net sales for the three months ended March 31, 2020 increased by $56.9 million or 19.0% to $356.6 million compared to $299.8 million in the same period in 2019. Net sales of wind blades increased by 21.4% to $336.3 million for the three months ended March 31, 2020 as compared to $277.0 million in the same period in 2019 despite the impact of COVID-19 on production levels at its China manufacturing facilities which impacted net sales by approximately $38 million.
The increase was primarily driven by a 10.8% increase in the number of wind blades produced during the three months ended March 31, 2020 compared to the same period in 2019 largely as a result of increased production at our Mexico facilities. This increase was also due to a higher average sales price due to the mix of wind blade models produced during the three months ended March 31, 2020 compared to the same period in 2019 as well as an increase in the year over year number of wind blades still in the production process at the end of the period.
Total cost of goods sold for the three months ended March 31, 2020 was $360.5 million and included $7.8 million related to lines in startup and $4.2 million of transition costs related to lines in transition during the quarter. This compares to total cost of goods sold for the three months ended March 31, 2019 of $301.2 million and included $16.1 million related to lines in startup and $2.1 million of transition costs related to lines in transition during the quarter.
General and administrative expenses for the three months ended March 31, 2020 totalled $9.5 million, or 2.7% of net sales, compared to $8.0 million, or 2.7% of net sales, for the same period in 2019.
Net loss for the three months ended March 31, 2020 was $0.5 million as compared to a net loss of $12.1 million in the same period in 2019. Adjusted EBITDA for the three months ended March 31, 2020 decreased to $1.3 million compared to $2.9 million during the same period in 2019. COVID-19 negatively impacted the three months ended March 31, 2020 Adjusted EBITDA by approximately $11 million primarily due to the temporary suspension of production at its China manufacturing facilities.
TPI already announced the withdrawal of its fiscal year 2020 financial guidance first issued on February 27, 2020 as a result of the uncertainty relating to (i) the rapidly evolving nature, magnitude and duration of the COVID-19 pandemic, (ii) the variety of measures implemented by governments around the world to address its effects and (iii) the impact on its manufacturing operations.